Management of Indeterminate Cystic Kidney Lesions: Review of Contrast-enhanced Ultrasound as a Diagnostic Tool

Indeterminate cystic kidney lesions found incidentally are an increasingly prevalent diagnostic challenge. Standard workup includes Bosniak classification with contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI). However, these tests are costly and not without risks. Contrast-enhanced ultrasound (CEUS) is a relatively new technique with lower risk of adverse events than iodine-containing contrast or gadolinium. In our review of the evidence for characterization of cystic kidney lesions with CEUS, CEUS displayed sensitivity (89%-100%) and negative predictive value (86%-100%) comparable to contrast-enhanced CT or MRI, with no decrease in specificity compared with CT and only a slight decrease compared with MRI.